A simple, effective and environmentally friendly green synthesis was demonstrated to obtain trimetallic Au/Pt/Ag nanoparticles using Lamii albi flos extract. The formed nanoparticles (NPs) were characterized by Ultraviolet–Visible, Fourier-Transform Infrared, Scanning Electron Microscopy, Transmission Electron Microscopy, and Atomic Force Microscopy measurements. The applied physicochemical methods indicated that the size of synthesized Au/Pt/Ag NPs was in the range of 35–40 nm. The antimicrobial activity of the obtained nanoparticles was assessed using Gram-positive, Gram-negative bacteria and yeasts, including standard strains of Staphylococcus aureus NCTC 4163, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Candida albicans ATCC 10231. Also, antibacterial and antibiofilm activities of novel nanoparticles were studied using clinical strains of Enterococcus spp. The obtained Au/Pt/Ag NPs revealed excellent antimicrobial effects against planktonic and sessile clinical strains of Enterococcus faecalis and Enterococcus faecium.

Introduction and objective: Pseudomonas aeruginosa is an opportunistic pathogen that causes difficult with treating infections, especially in the immunocompromised and patients with some underlying disease. The aim of the study is to assess the antibiotic resistance, biofilm formation, and...

Due to the rapidly increasing problem of antibiotic resistance in recent years, the use of phthalocyanines as photosensitizers with their superior properties in photodynamic antimicrobial therapy (PACT) applications has become important. In this study, magnesium(II) 1,4,8,11,15,18,22,25-octakis(4-[4-butoxycarbonylphenoxy]butyloxy)phthalocyanine was used in the demetalation reaction in trifluoroacetic acid, and subsequently subjected to metalation reaction in dimethylformamide with zinc(II) acetate and bis(benzonitrile)palladium(II) chloride towards zinc(II) and palladium(II) derivatives. Three phthalocyanines, including a demetalated one as well as two metalated, in the core with zinc(II) and palladium(II) were characterized using 1D and 2D NMR spectroscopy and mass spectrometry. In addition, all macrocycles were subjected to absorption and emission studies as well as photostability tests. In a photochemical study, zinc(II) and palladium(II) phthalocyanine complexes appeared to be efficient singlet oxygen generators. There were noted quantum yields of singlet oxygen generation for zinc(II) phthalocyanine derivative in DMF and DMSO at 0.55 and 0.72, whereas for palladium(II) complex at 0.73 and 0.77, respectively. Liposomal formulations of phthalocyanine derivatives were prepared, and their activity was evaluated against a broad spectrum of antibiotic-resistant microorganisms, such as methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (ESBL+), Candida albicans resistant to fluconazole, C. auris, and against dermatophytes. Phthalocyanine palladium(II) complex showed the highest bactericidal activity against all antibiotic-resistant microorganisms, including reducing C. auris growth at 3.54 log.

In the present study, the essential oils obtained by hydrodistillation of the organs of Eryngium maritimum and E. alpinum were analyzed by GC-FID-MS. The dominant constituents assessed in the essential oil of E. maritimum were germacrene D (45.2%) in the fruits; hexadecanoic acid (18.5%), menthol (16.8%), and menthone (10.9%) in the roots; 2,3,4-trimethylbenzaldehyde (11.3%) and germacrene D (10.5%) in the leaves; 2,3,4-trimethylbenzaldehyde (11.3%) in the shoot culture. In the case of E. alpinum, the main components of the leaf oil were: β-elemenone (10.3%), germacrone (5.8%), two selinadienes (7.1% and 6.7%), and 1,8-cineole (5.3%), which were not found in the oil from shoot culture, whereas the shoot culture oil was dominated by hexadecanoic acid (15.5%), spathulenol (7.5%), (E)-β-farnesene (4.9%), germacra-4(15),5,10(14)-trien-1α-ol (4.7%), and falcarinol (4.3%). The essential oils obtained from E. maritimum fruits and leaves of the intact plants, measured by the broth microdilution method, were the most active against T. mentagophytes and S. aureus. Moreover, the essential oil of leaves had the moderate activity against C. albicans and E. coli. The results showed that the chemical compositions of the essential oils differed decidedly between the two studied species and between the organs. Furthermore, the essential oil of E. maritimum may play an important role as antimicrobial agent.

A protocol for C. japonica micropropagation with a confirmation of genome size stability of the in vitro-propagated plantlets was developed. The highest number of shoots multiplied in vitro was obtained on Murashige & Skoog medium (MS) with 1.0 mg L−1 N6-benzyladenine plus 1.0 mg L−1 indole-3-acetic acid. The highest number of roots was observed for the shoots on MS with 15 g L−1 sucrose plus 1.0 mg L−1 indole-3-acetic acid. The acclimatization rate was significantly high. The qualitative HPLC analyses confirmed the presence of phenolic acids and flavonoids in the extracts. The extracts from both shoot cultures and the leaves from field-grown plants revealed antioxidant activity and they exhibited moderate antimicrobial activity. The conducted research confirmed the regeneration potential of genetically-stable plants of C. japonica under in vitro conditions, the ability of the plantlets to produce polyphenols as those present in field-grown plants, as well as their antioxidant potential.

Recently, the combined application of synergistic therapies for photodynamic antimicrobial chemotherapy has become important to obtain more efficient results. The synergism between two sensitizers, rose bengal (RB) and chlorin e6 (Ce6), excited by two different methods, was evaluated as a novel approach to both photodynamic and sonodynamic therapy against methicillin-resistant Staphylococcus aureus. The sonostability and singlet oxygen generation (with 1,3-diphenylisobenzofuran for RB and tetrathiafulvalene for Ce6) were measured under sonication (1 MHz, 3 W) using a spectrophotometer. RB and Ce6 remained stable during sonication. RB was a more efficient sonosensitizer than Ce6. The dual synergism between RB and Ce6 was noticed, achieving a >3 log reduction for molar ratios RB:Ce6 of 1:1 and 1:3, while, alone, the sensitizers excited with ultrasound and light, respectively, achieved only ca. a 1 log reduction.